MPA (Marine Protected Area) and MCA (Marine Control Area) sampings are done over three transects (three replicates) separated by 25m inside each zone. The chosen zones inside each area (MPA / MCA) match three different habitats:

• the outer slope at 10m of depth,
• the barrier reef at 200m off the crest reef inside the lagoon,
• and the border of the fringing reef that is closest to the channel, or when the channel does not exist, at the frontier between the barrier reef and the fringing reef.

In each station, surveys cover fish, substrate cover and benthic invertebrates populations.

The transects (tr) are positioned parallel to the shore or to the crest reef in the lagoon and on the outer slope. When the spurs on the outer slope are delimited by deep grooves, the transects are positioned in a triangle shape on an only spur (it is as such for MPA/MCA of Pihaena, E2B, Tiahura and Aroa) with tr 2 parallel (//) to the reef crest, tr 3 on the left hand side while looking at the coast and tr 1 on the right hand side.
Transects on the outer slope are at 10m of depth except on the spurs of the North coast (Pihaena, E2B, Tiahura, Aroa) where the beginning and the end of the transects vary between 7m and 12m.
The GPS point is taken above tr 2 on the outer slope and at the beginning tr 2 in the lagoon ( except in Aroa on the fringing reef where the GPS point is exceptionally at the start of tr 1).
The transects are numbered from 1 to 3 in the lagoon, tr 1 being on the right hand side when looking at the coast and the stake labeled "first stake" always being on the right hand side of the transect when looking at the coast.

The surveys are always done after 8am and before 4:30pm.

A sampling zone with its 3 replicates. The GPS coordinates of the MPA indicate the starting point of the middle transect (tr 2) which is unraveled turning the back to the beach. The third transect (tr 3) is then deployed 25m on the right hand side of tr 2, and the transect tr 1 25m on the left hand side of tr 2.

Survey frequency
From 2004 to 2009, the surveys were done on the same stations twice a year every 6 months around January-February (called warm or wet season) and July-August (called cold or dry season), and always at full moon.
From 2010 up to now, the surveys are only taken once a year during the warm / wet season (January to March).

Campaign number	Date (dd-mm-yyyy)	Periode
1	27-07 to 6-08-2004	cold
2	15-02 to 26-02-2005	warm
3	12-08 to 26-08-2005	cold
4	7-01 to 21-01-2006	warm
5	4-07 to 11-07-2006	cold
6	29-01 to 7-02-2007	warm
7	2007	cold
8	2008	warm
9	2008	cold
10	2009	warm
11	2009	cold
12	2010	warm
13	2011	warm
14	2012	warm
15	2013	warm
16	2014	warm
17	2015	warm
18	2016	warm